JP3991764B2 - Illumination device and projection display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lighting device and a projection display device, and more particularly to a configuration of a lighting device having excellent light utilization efficiency.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a projection type display device that synthesizes image light using a light modulation device such as a liquid crystal light valve and enlarges and projects the synthesized image light on a screen through a projection optical system including a projection lens or the like is known. In an illumination optical system used in this type of projection display device, light emitted from a light source such as a metal halide lamp is usually light having a random polarization state. However, in the case of a projection type liquid crystal display device using a liquid crystal light valve that uses polarized light, only one direction of polarized light is used for display. Therefore, if light from a light source is directly incident on the liquid crystal light valve, approximately half of the light is emitted. Is absorbed by the incident-side polarizing plate, and the light absorbed here is not used for display thereafter.
[0003]
Therefore, in the conventional projection-type liquid crystal display device, for the purpose of improving the light utilization efficiency, the polarization conversion means for aligning the light in a random polarization state from the light source with the unidirectional polarization used for display is provided with the light source and the liquid crystal light. It is installed between the valves. As the polarization converting means, a polarized beam splitter (hereinafter abbreviated as PBS) array is generally used. A PBS array is a combination of a plurality of PBSs having a polarization separation film and a reflection film and a phase difference plate such as a half-wave plate, and includes p-polarized light and s-polarized light contained in light from a light source ( One of the linearly polarized light) has a function of converting the polarization to align with the other polarized light.
[0004]
[Problems to be solved by the invention]
However, the polarization conversion means of the conventional projection display device using the PBS array has the following problems.
Since each PBS itself is an element with a certain size, the PBS array in which it is arranged in an array becomes quite large, making the recent projection display devices smaller, thinner and lighter. It will not meet the requirements of. Further, light must be incident on a position corresponding to the polarization separation film on the incident surface of the PBS array, and a lens system for condensing the light at that position is required. This complicates the configuration of the polarization conversion means. In addition, since the optical path lengths of the p-polarized light and the s-polarized light separated by the polarization separation film are different, there is a problem that the illumination conditions on the light valve are deviated and the light use efficiency is reduced.
[0005]
The present invention has been made to solve the above-described problems, and has an illumination device that is excellent in light utilization efficiency and can be reduced in size, thickness, and weight with a simple configuration, and the illumination device. It is an object of the present invention to provide a small, thin and light projection type liquid crystal display device.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an illuminating device of the present invention is an illuminating device including a light source and a polarization conversion unit that aligns light incident from the light source with polarized light in one direction. A reflection plate provided on the rear side with respect to the light emission direction of the light source body such that the surface on the side of the light source body is a reflection surface, the polarization conversion means is provided on the light emission side of the light source; A reflection type polarizing plate that transmits polarized light in a predetermined vibration direction and reflects polarized light in a vibration direction different from the vibration direction is provided.
[0007]
According to this configuration, since the reflective polarizing plate that transmits one polarized light (for example, p-polarized light) and reflects the other polarized light (for example, s-polarized light) is provided on the light emitting side of the light source, When light in a polarized state is incident on the reflective polarizing plate, for example, p-polarized light is transmitted through the reflective polarizing plate, and s-polarized light is reflected and returns to the light source side. And the light which returned to the light source side reflects with the reflecting plate provided in the back of the light source main body, and propagates again toward a reflection type polarizing plate. If it does so, the light which could not permeate | transmit the reflection type polarizing plate initially will reciprocate between a reflection type polarizing plate and a reflecting plate, unless a polarization state changes. However, in reality, the polarization state gradually changes as the light is repeatedly reflected, so that part of the light passes through the reflective polarizing plate, and all the unabsorbed light is eventually reflected. It penetrates the plate. Therefore, when this illuminating device is applied to a projection display device, the light initially reflected by the reflective polarizing plate will eventually pass through the reflective polarizing plate in a state of uniform polarization, and light from a liquid crystal light valve, etc. The light enters the modulation means. In this way, it is possible to realize an illuminating device with higher light utilization efficiency than in the past.
[0008]
In the illumination device of the present invention, a reflective polarizing plate is used as an element having a polarization conversion function instead of the conventional PBS array. As the reflective polarizing plate, for example, a film multilayer laminated polarizing plate can be used, which is completely different from the case of the PBS array, and can contribute to downsizing, thinning, and weight reduction of the apparatus. In the case of a reflective polarizing plate, light can be incident on the entire surface, and there is no need to collect light at a specific position unlike a PBS array. Therefore, it is not necessary to use a lens for the polarization conversion optical system, and the configuration is simplified. In addition, a wave plate used in a PBS array is not necessary, and the number of parts can be reduced.
[0009]
In the illuminating device of this invention, it is desirable to provide a phase difference plate between the light source and the reflective polarizing plate.
[0010]
According to this configuration, the polarization state is positively converted by the action of the phase difference plate, not the natural polarization change when the light is reflected on the reflection type polarizing plate or the reflection plate. The change in the polarization state during reciprocation between the reflective polarizing plate and the reflective plate becomes larger. As a result, the ratio of light passing through the reflective polarizing plate can be increased, and the light use efficiency can be further increased. Here, as a retardation plate, a retardation plate that does not generate a uniform retardation like a half-wave plate or a quarter-wave plate, but generates a phase difference that varies depending on a light transmitting position is used. Is desirable. According to this configuration, the light reciprocating between the reflection plate and the reflection-type polarizing plate is subjected to different phase modulation actions in the forward and backward directions, and the change in the polarization state becomes larger.
[0011]
Furthermore, it is desirable to provide a rod-shaped light guide or a tubular light guide whose inner surface is a reflection surface between the light source and the reflective polarizing plate. The “rod-shaped light guide” or “tubular light guide whose inner surface is a reflecting surface” is a so-called conventional rod lens.
[0012]
According to this configuration, the light guide (rod lens) not only performs the function of guiding the light emitted from the light source to the reflective polarizing plate, but also while the light passes through the light guide. The light reflected by the surface and reflected at various angles is also superimposed on the exit end face of the light guide, thereby achieving the function of uniforming the illuminance distribution of the light. That is, when the light is emitted from the illumination device, the polarization state is aligned in one direction, and the illuminance distribution is made uniform. Projection type display devices are usually equipped with uniform illumination means such as fly-eye integrators and rod integrators in order to make the illuminance distribution of the light source light uniform. Therefore, the uniform illumination means and the polarization conversion means can be used together.
[0013]
The reflective polarizing plate can be composed of a grid polarizer having a plurality of light reflectors arranged in stripes at a pitch smaller than the wavelength of incident light, in addition to the above-mentioned film multilayer laminated polarizing plate.
According to this configuration, since the reflective polarizing plate can be formed of an inorganic material, it has excellent heat resistance and light resistance. Therefore, it is suitable for use in a projection display device that is irradiated with high-luminance light.
[0014]
A projection display device according to the present invention is a projection display device including the illumination device according to the present invention, wherein the light source has a plurality of light source bodies that are capable of emitting color lights of different colors in a time sequential manner. A planar light source arranged in a curved surface, a light modulation means comprising a light valve driven in a time-sharing manner in synchronization with the emission timing of each color light emitted sequentially from the light source, and modulated by the light modulation means And projection means for projecting the emitted light.
[0015]
According to this configuration, since the illumination device of the present invention is provided, the projection display device can be reduced in size, thickness, and weight, and light use efficiency is improved. Power consumption can be reduced. Further, this projection type display apparatus adopts a driving method called “color sequential driving method”. Therefore, unlike a conventional three-plate projection display device using three light valves for each color light, only one light valve is required (single-plate method), and the illumination optical system for the light modulation means One system is sufficient. Further, since the color separation optical system and the color synthesis optical system are not required, the number of parts can be greatly reduced, the apparatus configuration can be simplified, and the cost can be reduced.
[0016]
Still another projection display device of the present invention is a projection display device including the illumination device of the present invention, wherein the light source is a plurality of planar light sources capable of emitting color lights of different colors, A plurality of light modulation means comprising light valves for modulating each color light emitted from the light source via the polarization conversion means; a color composition means for combining the color lights modulated by the plurality of light modulation means; and the color composition And projection means for projecting the light synthesized by the means.
[0017]
The projection display device of this configuration also includes the illumination device of the present invention, so that the projection display device can be reduced in size, thickness, and weight, and light use efficiency is improved, resulting in high brightness. However, unlike the projection type display device described above, a plurality of light valves are required. However, unlike the conventional apparatus, a plurality of light sources are configured to emit color lights of different colors, and a light valve is provided for each color light, so that no color separation means is required. As a result, the apparatus configuration is simplified as compared with the conventional apparatus. Further, since it is not necessary to synchronize the driving of the light source and the light valve as in the apparatus described above, the driving does not become complicated, and the light valve does not need to be as fast as the response speed.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
In this embodiment, an example of a color sequential driving projection type color liquid crystal display device is shown. FIG. 1 is a schematic diagram showing the overall configuration of the projection display device 1, in which 2 is an LED array (light source), 3 is a phase difference plate, 4 is a taper rod lens array, 7 is a rod lens array, 8. Is a reflection type polarizing plate, 5 is a liquid crystal light valve (light modulation means), and 6 is a projection lens.
[0019]
As shown in FIG. 1, the projection display device 1 according to the present embodiment has a plurality of light emitting diodes (only four are shown in FIG. 1 for easy viewing). LED array 2 in which 14R, 14G, and 14B (Light Emitting Diodes, hereinafter abbreviated as LEDs) are arranged, phase difference plate 3 provided on the emission side of LED array 2, and each LED 14R, 14G, and 14B. Tapered rod lens array 4 and rod lens array 7 for uniformizing the illuminance of each color light, reflection type polarizing plate 8 that performs polarization conversion of light emitted from rod lens array 7, and incident from reflection type polarizing plate 8 A liquid crystal light valve 5 that synthesizes an image by modulating each color light, and a projection lens 6 that enlarges and projects an image synthesized by the liquid crystal light valve 5 onto a screen 9 are schematically configured. Among these, the illuminating device of this Embodiment is comprised by the LED array 2, the phase difference plate 3, the taper rod lens array 4, the rod lens array 7, and the reflection type polarizing plate 8. FIG. In addition, FIG. 2 is a figure which takes out and shows only the part corresponding to one LED among the illuminating devices of this Embodiment.
[0020]
The LED array 2 is connected to a light source driving circuit 10, and the timing at which each LED 14 R, 14 G, 14 B emits light is controlled by this light source driving circuit 10, and for example, R, G, B, R, and so on from each LED 14 R, 14 G, 14 B G, B,... Can emit light of different colors in time sequence. Further, in FIG. 2, the right side surface of each LED 14R, 14G, 14B is a light emitting surface, and light is emitted rightward from each LED 14R, 14G, 14B. Then, on the rear side (left side of the LED in FIG. 2) with respect to the light emitting direction of each LED 14R, 14G, 14B, a curved reflector 15 made of a metal film or the like is a surface on the side with respect to each LED 14R, 14G, 14B. Is installed as a reflective surface.
[0021]
In the taper rod lens array 4, a plurality of taper rod lenses 16 made of wedge-shaped glass columns are arranged corresponding to the LEDs 14R, 14G, and 14B via the phase difference plate 3. In FIG. 2, the left side surface of the tapered rod lens 16 is the incident end surface, and the right side surface is the outgoing end surface. Each taper rod lens 16 has a tapered shape that widens from the incident end face side toward the outgoing end face side. Similarly, the rod lens array 7 provided on the exit end face side of the taper rod lens array 4 includes a plurality of rod lenses 17 made of glass columns having the same diameter on the entrance end face side and the exit end face side, and each LED 14R, 14G, 14B (each taper rod lens 16) is arranged correspondingly.
[0022]
The phase difference plate 3 is for increasing the change in the polarization state of light reciprocating between the reflective polarizing plate 8 and the reflective plate 15 as will be described later. This phase difference plate 3 is meaningful in that the polarization state is changed more greatly than by giving some phase difference to the light passing through the phase difference plate 3 compared with the case where there is nothing. Therefore, it is not limited to those having specific phase difference values such as ½ wavelength and ¼ wavelength. Further, the phase difference plate 3 does not generate a uniform phase difference like a half-wave plate or a quarter-wave plate, but a phase difference plate that generates a phase difference that varies depending on the position where the light is transmitted. It is desirable. In that case, the light reciprocating between the reflection plate 15 and the reflection type polarizing plate 8 is subjected to different phase modulation actions in the forward and backward directions, and the change in the polarization state can be further increased.
[0023]
The reflective polarizing plate 8 has a function of transmitting, for example, one of p-polarized light and s-polarized light (linearly polarized light) out of light in a random polarization direction emitted from the LED array 2 and reflecting the other. Yes. With this function, light having the polarization direction aligned in one direction is always emitted from the reflective polarizing plate 8. As the reflective polarizing plate 8, for example, a film multilayer laminated polarizing plate can be used, or a reflective polarizer using a grid polarizer made of an inorganic material can be used.
[0024]
As an example of the latter, as shown in FIG. 5, a large number of ribs 24 (light reflectors) made of a light reflective metal such as aluminum are formed on the glass substrate 25 at a pitch smaller than the wavelength of incident light. Grid polarizers. That is, the reflective polarizer 8 has Al ribs 24 having different refractive indexes and air alternately arranged in stripes at a pitch smaller than the wavelength of incident light, so that the intensity of transmitted light and reflected light is It behaves differently depending on the polarization state, and as a result, it functions as a polarizer. With this configuration, when random polarized light is incident on the surface on which the Al rib 24 is formed, S-polarized light oscillating in a direction parallel to the extending direction of the Al rib 24 is reflected, and the extending of the Al rib 24 is performed. P-polarized light that vibrates in the direction perpendicular to the direction (the direction in which the Al ribs are arranged) is transmitted.
[0025]
In the illumination device of the present embodiment, the light emitted from each LED 14R, 14G, 14B has a luminance distribution in which the luminance at the center of the LED is high and the luminance at the peripheral portion is low. However, since the tapered rod lens 16 and the rod lens 17 are sequentially provided on the emission side of the LEDs 14R, 14G, and 14B, the incident light from the LEDs 14R, 14G, and 14B is repeatedly reflected on the inner surfaces of the lenses 16 and 17, At the time of exit from the exit end face of the rod lens 17, the illuminance is uniform.
[0026]
Then, when light in a random polarization state with uniform illuminance is incident on the reflective polarizing plate 8, for example, p-polarized light is transmitted through the reflective polarizing plate 8, and s-polarized light is reflected, and the LEDs 14R, 14G, and 14B are reflected. Return to the side. Then, the light returned to the LEDs 14R, 14G, and 14B is reflected by the reflecting plate 15 and travels toward the reflective polarizing plate 8 again. Then, the light that could not pass through the reflective polarizing plate 8 first reciprocates between the reflective polarizing plate 8 and the reflective plate 15 as long as the polarization state does not change. The polarization state changes little by little as it repeats. Further, in the present embodiment, not only is the natural polarization change at the time of reflection, but also the phase difference plate 3 is provided on the optical path between the reflection type polarizing plate 8 and the reflection plate 15 so that the light is phase difference. Since the polarization state is forcibly changed when passing through the plate 3, the change in the polarization state becomes larger. Therefore, a part of the light initially reflected by the reflective polarizing plate 8 can pass through the reflective polarizing plate 8 while reciprocating between the reflective polarizing plate 8 and the reflective plate 15.
[0027]
On the other hand, the liquid crystal light valve 5 uses a TN mode active matrix transmission type liquid crystal cell 31 using a thin film transistor (hereinafter abbreviated as TFT) as a pixel switching element. An incident-side polarizing plate 32 and an emitting-side polarizing plate 33 are provided on the outer surface of the liquid crystal cell 31 so that their transmission axes are orthogonal to each other. For example, p-polarized light incident on the liquid crystal light valve 5 is converted into s-polarized light and emitted in the off state, while light is blocked in the on state. The LED array 2, the phase difference plate 3, the taper rod lens array 4, the rod lens array 7, the reflective polarizing plate 8, and the liquid crystal light valve 5 that constitute the above-described illumination device may be arranged apart from each other. In order to reduce the size and thickness of the device, it is desirable to arrange them in close contact with each other.
[0028]
As shown in FIG. 1, the liquid crystal light valve 5 is connected to a liquid crystal light valve drive circuit 11, and the liquid crystal light valve drive circuit 11 moves the liquid crystal light valve 5 in time-sequential manner corresponding to each incident color light. It has a structure that can be driven. Further, the projection display device 1 of the present embodiment is provided with a synchronization signal generation circuit 12, which generates a synchronization signal SYNC to drive the light source drive circuit 10 and the liquid crystal light valve. By inputting to the circuit 11, the timing of emitting the color light from each LED 14 R, 14 G, 14 B and the timing of driving the liquid crystal light valve 5 corresponding to the color light can be synchronized.
[0029]
That is, in the projection type display device 1 of the present embodiment, one frame is time-divided, and the R, G, B color lights are emitted from the LEDs 14R, 14G, 14B in time order, and the color lights are emitted from the LEDs 14R, 14G, 14B. Is synchronized with the timing at which the liquid crystal light valve 5 is driven, so that the liquid crystal light valve 5 is driven sequentially in time according to the color light emitted from each LED 14R, 14G, 14B. , 14B by outputting an image signal corresponding to the color light emitted from 14B, it is possible to synthesize a color image.
[0030]
The projection type display apparatus of the present embodiment employs a so-called “color sequential driving (color sequential) system”. Therefore, unlike the conventional three-plate projection display device using three liquid crystal light valves for each color light, only one liquid crystal light valve is required (single-plate method), and the light modulation means is illuminated. One optical system is sufficient. Further, since the color separation optical system and the color synthesis optical system are not required, the number of parts can be greatly reduced, the apparatus configuration can be simplified, and the cost can be reduced.
[0031]
In the present embodiment, as described above, the reflective polarizing plate 8 is provided on the exit side of the lighting device, and the reflective plate 15 is provided behind the LEDs 14R, 14G, and 14B. Then, the reflected light is transmitted through the reflective polarizing plate 8 in a state where the polarization state is kept constant while repeating reflection with the reflection plate 15, and is incident on the liquid crystal light valve 5. In this way, it is possible to realize an illuminating device with higher light utilization efficiency than in the past.
[0032]
In the illumination device of the present embodiment, a reflective polarizing plate 8 is used as an element having a polarization conversion function instead of the conventional PBS array. When a commercially available polarizing film is used as the reflective polarizing plate 8, it can contribute to the reduction in size, thickness, and weight of the apparatus. When the reflective polarizer 8 made of a structural birefringent material is used, it is excellent in light resistance and heat resistance, and is particularly suitable for a projection display device. In the case of the reflective polarizing plate 8, unlike the PBS array, light can be incident on the entire surface, and it is not necessary to collect the light at a specific position. Therefore, it is not necessary to use a lens for the polarization conversion optical system, and the configuration is simplified. In addition, a wave plate used in a PBS array is not necessary, and the number of parts can be reduced. That is, it is possible to realize a very compact illuminating device having both a uniform illumination function and a polarization conversion function.
[0033]
[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to FIG.
Although the present embodiment is also an example of a projection type color liquid crystal display device, the first embodiment is an example of a single plate method of a color sequential drive method, whereas in the present embodiment, a three plate method is used. An example is shown. FIG. 6 is an enlarged view showing a schematic configuration of the projection display device. In FIG. 6, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0034]
In the first embodiment, the LED array 2 in which the LEDs 14R, 14G, and 14B that can emit light of different colors of R, G, and B are used as the light source is used in the same plane. In the projection type liquid crystal display device 36, as shown in FIG. 6, an LED array 2R in which LEDs 14R capable of emitting R colored light are arranged in the same plane, and an LED 14G capable of emitting G colored light are arranged in the same plane. Three LED arrays 2B, in which LEDs 14B capable of emitting the color light of the LED arrays 2G and B are arranged in the same plane, are used as the planar light source. And the phase difference plate 3, the taper rod lens array 4, the rod lens array 7, and the reflective polarizing plate 8 are respectively arranged on the emission side of each LED array 2R, 2G, 2B, as in the first embodiment. ing. Therefore, the projection display device of the present embodiment has three systems of illumination devices for each color light.
[0035]
A liquid crystal light valve 5 for modulating each color light of R, G, B is provided on the emission side of the reflective polarizing plate 8 for each color light. Then, the three color lights modulated by the liquid crystal light valves 5 are configured to enter the cross dichroic prism 25 (color synthesis means). This prism 25 is formed by bonding four right-angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface. These dielectric multilayer films combine the three color lights Lr, Lg, and Lb to form light representing a color image. The color-synthesized light is projected onto the screen 9 by the projection lens 6 and an enlarged image is displayed.
[0036]
Unlike the apparatus of the first embodiment, the projection display apparatus of the present embodiment requires three liquid crystal light valves 5. However, unlike the conventional device, the three illumination devices are configured to emit color lights of different colors, and the liquid crystal light valve 5 is provided for each color light, so that it is like a dichroic mirror in the conventional device. No need for color separation means. As a result, the apparatus configuration is simplified as compared with the conventional apparatus. Further, since it is not necessary to synchronize the driving of the LED arrays 2r, 2g, 2b and the liquid crystal light valve 5 as in the apparatus of the first embodiment, the driving is not complicated and the response speed of the liquid crystal light valve is also so much. You don't need to be fast.
[0037]
Also in the present embodiment, it is possible to realize a lighting device with high light utilization efficiency by providing the reflective polarizing plate 8 on the emission side of the lighting device and the reflector 15 behind the LEDs 14R, 14G, and 14B. It is possible to obtain the same effect as the first embodiment in that the configuration of the polarization conversion optical system is simplified by eliminating the need for the condensing lens, and the number of components can be reduced by eliminating the need for the wavelength plate. it can.
[0038]
The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, as shown in FIG. 2, an illumination device including the retardation plate 3, the taper rod lens 16, the rod lens 17, and the reflective polarizing plate 8 in order on the emission side of the LEDs 14R, 14G, and 14B. Although illustrated, instead of this configuration, for example, as shown in FIG. 3, a configuration in which the rod lens 17 is omitted from the configuration of FIG. Thereby, an illuminating device can be made thinner. Furthermore, as shown in FIG. 4, the taper rod lens 16 may be omitted, and the phase difference plate 3 and the reflective polarizing plate 8 may be directly laminated on the emission surface of the LEDs 14R, 14G, and 14B. As a result, the lighting device can be significantly reduced in thickness.
[0039]
In the above embodiment, the LEDs 14R, 14G, and 14B and the rod lenses 16 and 17 correspond to 1: 1. However, it is not always necessary to correspond to 1: 1. One rod lens may correspond. Further, although a plurality of LEDs 14R, 14G, and 14B arranged in an array is used as a light source, only one LED may be used as long as a necessary and sufficient amount of light can be obtained. In the above embodiment, an example in which the lighting device of the present invention is used for a projection display device is shown, but it can also be used for a direct-view display device.
[0040]
【The invention's effect】
As described above in detail, according to the present invention, the light initially reflected by the reflective polarizing plate is also transmitted through the reflective polarizing plate in a state where the polarization state is constantly uniform, such as a light valve. The light is incident on the light modulation means. In this way, it is possible to realize an illuminating device with higher light utilization efficiency than in the past. Moreover, in the illumination device of the present invention, a reflective polarizing plate is used in place of the conventional PBS array as the polarization conversion element, which can contribute to miniaturization, thickness reduction, and weight reduction of the device. It is suitable for use in an apparatus.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a projection display device according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view showing only a portion corresponding to one LED of the illumination device in the projection display device.
FIG. 3 is a sectional view showing another example.
FIG. 4 is a sectional view showing still another example.
FIG. 5 is a perspective view showing an example of a reflective polarizing plate used in the illumination device.
FIG. 6 is a schematic configuration diagram showing a projection display device according to a second embodiment of the present invention.
[Explanation of symbols]
1 Projection display
2 LED array (light source)
3 Phase difference plate
4 Tapered rod lens array
5 Liquid crystal light valve (light modulation means)
6 Projection lens
7 Rod lens array
8 reflective polarizing plate
14R, 14G, 14B LED (light source body)
15 Reflector
16 Tapered rod lens
17 Rod lens

Claims (5)

An illumination device comprising a light source and polarization conversion means for aligning light incident from the light source with polarized light in one direction,
A light emitting diode, a light source side surface to said light emitting diode is provided with a reflecting plate provided on the rear side with respect to the light emitting direction of the light emitting diode so that the reflecting surface,
A polarization conversion means provided on a light emitting side of the light source, and including a reflective polarizing plate that transmits polarized light in a predetermined vibration direction and reflects polarized light in a vibration direction different from the vibration direction;
A phase difference plate that is provided between the light source and the reflective polarizing plate and generates a phase difference that varies depending on a position through which light passes;
A rod-shaped first light guide or a tubular tube having a reflection surface on the inner surface, which is provided between the light source and the reflective polarizing plate and has a taper shape that widens from the incident end surface side to the output end surface side. A first light guide,
The illumination device , wherein the light emitting surface of the light emitting diode of the light source, the retardation plate, the first light guide, and the reflective polarizing plate are disposed in close contact with each other. An illumination device comprising a light source and polarization conversion means for aligning light incident from the light source with polarized light in one direction,
A light source comprising: a light emitting diode; and a reflector provided on the rear side with respect to the light emitting direction of the light emitting diode such that a surface on the side of the light emitting diode becomes a reflecting surface;
A polarization conversion means provided on a light emitting side of the light source, and including a reflective polarizing plate that transmits polarized light in a predetermined vibration direction and reflects polarized light in a vibration direction different from the vibration direction;
A phase difference plate that is provided between the light source and the reflective polarizing plate and generates a phase difference that varies depending on a position through which light passes;
A rod-shaped first light guide or a tubular tube having a reflection surface on the inner surface, which is provided between the light source and the reflective polarizing plate and has a taper shape that widens from the incident end surface side to the output end surface side. A first light guide;
Provided between the first light guide and the reflective polarizing plate, and a second light guide having the same diameter on the incident end face side and the exit end face side,
The light emitting surface of the light emitting diode of the light source, the retardation plate, the first light guide, the second light guide, and the reflective polarizing plate are disposed in close contact with each other. apparatus.   3. The illumination device according to claim 1, wherein the reflective polarizing plate includes a grid polarizer having a plurality of light reflectors arranged in a stripe pattern with a pitch smaller than the wavelength of incident light. A projection display device comprising the illumination device according to any one of claims 1 to 3,
The light source is a planar light source in which a plurality of light source bodies capable of emitting color lights of different colors in time sequence are arranged in a planar shape or a curved shape,
A light modulation unit including a light valve driven in a time-sharing manner in synchronization with the emission timing of each color light emitted sequentially from the light source; and a projection unit for projecting light modulated by the light modulation unit. A projection display device characterized by that. A projection display device comprising the illumination device according to any one of claims 1 to 3,
The light source is a plurality of planar light sources capable of emitting different color lights.
A plurality of light modulation means comprising light valves for modulating each color light emitted from the light source through the polarization conversion means; a color synthesis means for synthesizing the color lights modulated by the plurality of light modulation means; and the color synthesis. A projection display device comprising: projection means for projecting light synthesized by the means.

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